Lecture 2: Jan. 23, 2006

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Lecture 2Jan. 23, 2006

• Transmission genetics
• Principle of segregation

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Sample problem
5-ATGCCCTGCAGTACCATGACGCGTTACGCAGCTGATCGAAACGCGTA
TATATGCC-3 3-TACGGGACGTCATGGTACTGCGCAATGCGTCGACT
AGCTTTGCGCATATATACGG-5
The restriction site for the enzymes PstI is
5-CTGCA?G-3 If the enzyme PstI was used to cut
the above DNA, what fragments would result?
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The traits studied by Mendel
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Mendels Results for Monohybrid Crosses
Parental traits F1 trait Number of F2 progeny F2 ratio
Round x wrinkled (seeds) Round 5474 round, 1850 wrinkled 2.961
Yellow x green (seeds) Yellow 6022 yellow, 2001 green 3.011
Purple x white (flowers) Purple 705 purple, 224 white 3.151
Inflated x constricted (pods) Inflated 882 inflated, 299 constricted 2.951
Green x yellow (unripe pods) Green 428 green, 152 yellow 2.821
Axial x terminal (flower position) Axial 651 axial, 207 terminal 3.141
Long x short (stems) Long 787 long, 277 short 2.841
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Explanation of the 31 phenotypic ratio of
dominant recessive